The invention relates to plumbing and, more particularly, to a leveling and elevation adapter for the grate of a floor drain. That is, the adaptor not only provides for leveling adjustment of the grate relative to the plane of the floor surface, but also elevation adjustment as well.
Floor drain construction has suffered from a longstanding problem that has existed for a long time, and, persists today. The problem is as follows. So often, the grate of a floor drain sits in its own shallow depression below the grade of the surrounding floor surface. That is, the grate of the floor drain may sit in a depression or recess that is a quarter inch to half inch (˜6 to ˜12 mm) deep below the grade of the floor surface. This shallow depression in the floor surface presents a trip hazard.
The inventor hereof is aware that, nowadays, there is heightened sensitivity to floor drains functioning as trip hazards. The parties who are now more sensitive to this issue of trip hazards includes not only managers of present day construction sites, but also, owners of aging commercial or institutional buildings as well. It is not known if this new sensitivity to trip hazards is driven by the American with Disabilities Act, or other current pressures, but the sensitivity seems more prevalent nowadays than in the past.
FIGS. 1 through 4 comprises a sequence of views showing how this problem develops during construction of a floor drain 105-108, both according to how construction is practiced today as well as how it has been practiced for over many many years previously. FIG. 1 shows a floor drain grate 108 making its appearance through a concrete slab 120 fresh after a pour. FIG. 2 is a sectional view taken along line II-II in FIG. 1, except showing an earlier time during the construction process, earlier than the time of FIG. 1. FIG. 3 is a view comparable to FIG. 1 except showing the result of the tile-workers having placed tile pieces 122 over the concrete slab 120 and prior to grouting the tile pieces together. FIG. 4 is a section view comparable to FIG. 2 except showing the state of things in FIG. 3.
The following description of this floor construction process entails the involvement of three different contractors (or trade skills):—plumbers, concrete workers, and tilers. At some original time, plumbers came through the construction site and laid all the plumbing for the drainwater piping 112 and floor 105-108 drains across the floor layout before the concrete slab 120 was ever poured. For a big commercial or institutional floor, there might be numerous drains 105-108 distributed in some array or some pattern as called out by the floor plan. As can be imagined by reference to FIG. 2, there would have been a distributed array of PVC risers 112 sticking up like so many small stumps across the floor layout, each crowned with a floor drain 105-108.
The floor drain 105-108 illustrated in the drawings is a product of the Jay R. Smith Mfg. Co. (founded in 1926 in New York City). However, it is believed both that the design particulars of this floor drain 105-108 are pretty similar to those of other manufacturers, and also that, the design particulars are (for the most part) irrelevant to the invention.
This floor drain 105-108 comprises a cast iron body 105, which is situated directly on top of the PVC riser 112, a cast iron reversible (ie., invertible) flashing collar 106 secured to the cast iron body 105 by three collar bolts 114 (only one shown), a strainer head 107 that threads into the flashing collar 106 by 3¾ inch 12 pitch thread, and, a grate 108 sitting in a seat 116 for it in the strainer head 107.
The inventor hereof has heard the combination of the body 105 and flashing collar 106 assembled together as the “sump” 105-106 or “sump assembly” 105-106.
Before the concrete pour, the plumbers make one last walk through the floor layout. Mainly, they check to see if the grates 108 are (a) in position, (b) level and (c) at the specified elevation. Many plumbers furthermore cover each grate 108 with duct tape 124 or the like to prevent wet concrete from seeping in. After that, all is ready for the concrete workers.
The concrete slab 120 is typically poured over the floor layout from cement mixer trucks or the like (not shown). The concrete pour progresses across the floor layout in a wave or series of waves. It is one of the jobs of the concrete workers to contain the momentum of those waves. That is, a concrete wave can easily gather enough momentum to barrel over the forms that are meant to dam it. However, a concrete wave with a whole lot less momentum than that can easily tilt the PVC riser 112 over to be a little crooked, and hence make the drain 105-108 uneven.
And once that tilt is introduced, there is little possibility of straightening out the PVC riser 112 in that matrix of the wet concrete. Hence the tilt, and unevenness, remain.
Moreover, some pour jobs are done where the concrete workers try to produce a little rise between drains 105-108, with a gentle downslope into the drains 105-108 (not shown). While that kind of concrete work is skillful business, it just aggravates the likelihood that the grate 108 will sit in the bottom of a depression that could likely become a trip hazard.
In any event, FIG. 2 shows the result of what so typically happens after the concrete slab 120 hardens. The floor drain 105-108 is a little tilted, with the grate 108 lying at an elevation a little below surface grade of the concrete slab 120. Indeed, concrete pour would have lapped over and onto the duct-tape 124 covered grate 108, and left the grate 108 with a thin covering of hardened concrete (not shown). Someone would have come back along afterwards (not necessarily the plumbers) and gently tapped out by hammer that thin covering of concrete (not shown). As result, there is sort of a ragged concrete rim 126 surrounding the grate 108.
To return to FIG. 2, it shows the following. Once the concrete slab 120 hardened, the following features are permanently cemented in place:—namely, the PVC riser 112, the cast iron body 105, the flashing collar 106, and the strainer head 107. Hence it is impossible to straighten the PVC riser 112 to become vertical again. Moreover, it also impossible to twist the strainer head 107 in or out of its threaded connection with the flashing collar 106. The wet concrete pour flowed into the exposed thread of the strainer head 107, and other exposed features of the flashing collar 106 and cast iron body 105. Once the concrete hardens, these features are rigidly cemented in place in the hardened concrete.
There is no adjustability after the concrete hardens. Also, there probably would be no practical opportunity to adjust the drains 105-108 while the concrete is wet and curing.
FIG. 1 shows the grate 108 peeking through the concrete slab 120, both after the thin covering (not shown) of hardened concrete has been tapped off the duct tape 124 and after the duct tape 124 has been peeled off. As FIG. 1 shows, the grate 108 sits in a mini depression in the concrete slab 120. The depth of this depression will be increased if the construction plans call for covering the concrete slab 120 with tile pieces 122 or the like.
And FIGS. 3 and 4 show exactly that. Adding tile pieces 122 around the grate 108 just increases the depth of the depression in the tile floor 128 down to the top of the grate 108. The potential trip hazard made to pedestrians across the tile floor 128 has just been made greater. The depression around the grate 108 has just simply been made deeper.
Pause can be taken now for applicant to remark on the following prior art disclosures.
U.S. Pat. No. 7,964,095—Graybeal discloses an adjustable floor drain. The Graybeal drain has a strainer head 20, a grate 40, and an interposed adjustment ring 30 which can be elevated relative to the strainer head 40 by elevating screws 31. See FIGS. 2 and 2b therein. The document recites in the last two paragraphs of the description (in part):                The installation and use of the floor drain can now be considered. After the vertical pipe (with or without a separate fitting) are set in place, and before the concrete floor is poured, the flanged cylindrical body [20] (with or without the ring [30] and grate [40] in place) is connected to the pipe or fitting. The elevating screws [31] of the body are preferably screwed in (lowered) as far as possible initially. A disposable cover is put into place to prevent concrete from entering the interior of the floor drain. The concrete floor is then poured and finished.        After the concrete floor has hardened, the disposable cover is removed. If not already in place, the ring [30] is then set in place on the flange [23] and the elevating screws [31] are adjusted by unscrewing (raising) them to make the top of the ring [30] perfectly flush with the surrounding floor. It can be appreciated that the adjustability range is increased as the length of the elevating screws [31] increases . . . .        
With reference to FIG. 2b in Graybeal, the space below the horizontal flange 23 of the strainer head 20 is going to be filled with hardened concrete. Graybeal has pre-drilled and pre-tapped his holes 31 and 32 as a manufacturing step for strainer head 20 before the strainer head 20 is cemented into hardening concrete.
Drilling and tapping such holes cannot be done after the concrete pour has hardened. Accordingly, the design concept of Graybeal cannot be used to retro-fit existing floor drains in aging commercial or institutional buildings that do not have Graybeal-style pre-drilled and pre-tapped horizontal flanges 23 in strainer heads 20.
Moreover, Graybeal asserts in the above passage that, “It can be appreciated that the adjustability range is increased as the length of the elevating screws [31] increases.” Applicant is skeptical about that assertion.
For the Graybeal design to work, there is the time before the concrete pour where Graybeal has to pre-install his elevating screws 31 into the horizontal flange 23 of the strainer head 20 such that “The elevating screws [31] of the body are preferably screwed in (lowered) as far as possible initially.” In other words, Graybeal leaves the bottom ends of his elevating screws 31 (see FIG. 2b thereof) exposed to being encased in the matrix of the wet concrete. When the wet concrete hardens, the bottom ends of elevating screws 31 are going to be cemented solid into the hardened concrete.
It has been the inventor's experience that hardened concrete has, indeed, a highly secure grip on encased features. There is a question as to, how much grip length on (for example) a one-quarter inch normal screw thread can be cemented solid into hardened concrete before the screw can never be untwisted out without the thread being fouled, or the screw snapping apart.
It surely is unrealistic to hope that any appreciable length one-quarter inch normal screw thread can be cemented into hardened concrete and thereafter be untwisted out without irreparable scarring to the screw thread, or worse, without snapping the screw in two.
U.S. Pat. No. 4,883,590—Papp also discloses an adjustable floor drain. The Papp floor drain appears to be a proprietary design unique to Papp and not an insert to a standardized design typical of the industry and typical of major producers in the industry such as (and without limitation) the Jay R. Smith Mfg. Co.
The Papp design has a singular outer body 13 which combines the features and functions of the conventional cast iron body 105 and flashing collar 106 shown in FIGS. 2 and 4 hereof.
Conversely, the Papp design has a pair of components which provide the features and functions of the conventional strainer head 107 shown in FIGS. 2 and 4 hereof:—namely, an externally-threaded sleeve 15 (with a spherical ball-seat surface 20) and a ring 17 (with lower spherical ball surface 18) (albeit, the Papp sleeve 15 and ring 17 provide some additional functionality over a conventional strainer head 107, as described next in part).
The threading of the Papp cylindrical sleeve 15 into the Papp outer body 13 provides elevation adjustment. The gyroscopic leveling of the Papp ball-formed ring 17 into (the ball seat 20 of) the Papp sleeve 15 provides leveling adjustment. The whole premise for the Papp design to work depends on, again and like Graybeal, anticipating and nullifying the cementing effects of hardening concrete.
Like the conventional drain design of Jay R. Smith Mfg. Co. and others, Papp does pre-install and pour wet concrete around the his equivalent of the cast iron body (105) and flashing collar (106), eg., the Papp outer body 13. Unlike the conventional design of Jay R. Smith Mfg. Co. and others, Papp leaves removed his equivalent of the strainer head (107) (eg., the Papp sleeve and ring 15 and 17). Papp keeps wet concrete from pouring into his open outer body 13 by means of a cardboard cylindrical shield 25. The cardboard cylindrical shield 25 leaves a clear and free-of-concrete column above the internal thread of the outer body 13 into which the external thread of the sleeve 15 can be twisted into:—once the cardboard shield has been plucked out of the hardened concrete.
It surely is unrealistic to hope that any appreciable vertical length of cylindrical cardboard shield can be plucked out of hardened concrete. Regardless, the Papp design does not interface with nor allow the retro-fitting of existing drains on aging commercial or institutional buildings.
What is needed is an improvement which will overcome the shortcomings of the prior art.
A number of additional features and objects will be apparent in connection with the following discussion of the preferred embodiments and examples with reference to the drawings.